1. Field of the Invention
This invention relates to a photographic film assemblage containing film of the self-developing or instant type.
2. Description of the Prior Art
This invention relates to a photographic film assemblage including a cannister for initially housing a film cassette containing a roll of film, preferably of the 35 mm instant or self-developing transparency type, and more particularly, to such a film assemblage which is constructed in a manner that facilitates the processing of the film. It is known that a film assemblage including a film cassette containing a length of film may be placed in a camera, the film withdrawn from the film cassette and photographically exposed, and the exposed film rewound and processed in a film processor specially adapted for use with the film assemblage. Examples of such systems can be found in U.S. Pat. Nos. 4,291,966, 4,212,521, 4,145,133 and 3,260,186. While these systems have their own special advantages, the separate processor adds to the cost of the system, requires the proper positioning of the film cassette within the processor, and/or the threading of the film leader to a film take-up spool.
The requirement of a separate film processor has been obviated by using the film cassette as the chamber in which the film is processed. Examples of such systems are shown in U.S. Pat. Nos. 4,374,195, 4,283,134, 4,265,525, 3,667,361 and in disclosure No. 19219 on pages 132-134 of the April 1980 edition of Research Disclosure. However, each of these systems has at least one feature which detracts from its use in the processing of a single roll of film. For example, the systems disclosed in the '134 and '525 patents are not readily adapted for use with the processing of a roll of film, vis-a-vis the processing of individual planar type film units. While the system disclosed in the '361 patent relates to the processing of roll film, the cassette's volume is relatively large because of the separate chamber containing the processing fluid, thus detracting from its use in compact cameras. Further, the systems disclosed in the '195 patent and in the Research Disclosure article teach the placement of processing fluid container(s) in a chamber defined by what appears to be a conventional film spool and the interior surfaces of a film cassette. Such placement requires an unnecessarily large volume chamber for a given length of film or conversely the length of film stored in the chamber must be decreased in order to accommodate the volume of the processing fluid container(s). Still further, most of these systems teach the rupturing of the processing fluid container(s) while it is located exteriorly of the film cassette and while the film cassette is in a camera, thus possibly subjecting camera parts to the corrosive effects of any processing fluid which may be expressed from between layers of the film.
The prior art also teaches that the cannister or can which initially functions to house a film cassette containing a roll of fresh, unexposed film may also be used to hold the film cassette during processing of the film. More specifically, pages 27-29 of the paperback book entitled "The Man Who Fell To Earth" by Walter Tevis, published in 1963 by Fawcett Publications Inc. discloses a film assemblage having a cannister or can in which is located a supply of processing material, and a film cassette containing a roll of 35 mm self-developing color film. After the film has been photographically exposed, it is returned to the can and the can's cover replaced. A button in the cover is then depressed to process the film. However, this teaching is completely silent as to the location of the processing material or how it is able to enter the film cassette and contact the exposed film so as to initiate the formation of visible images therein.
From the foregoing it can be seen that there is a need for a simple and inexpensive means for facilitating the processing of a roll of photographically exposed film.